A couple of years ago we booked through www.villadeals.com which was part of Thomson we booked a huge villa in Portinax (Ibiza) for approx 200.00 in August. The Villa was in the 'magic of spain' brochure and should have cost at least 1500.00 for that week! We even had a welcome food pack and our own pool! We got some friends to come with us and split the cost booking cheap flights ourselves, it worked out cheaper than a package deal.
It's v hard to find details without specific dates and requirements!
Just had a quick google and found flights to Faro from Gatwick with expedia - £61 each (+ taxes though) - easyjet from Gatwick to Athens looks similar - that's each way, each, though. Not cheap at all.
What about driving to Southern France? Would be much cheaper...